Heating system and control means therefor



Nov. 10, 1942.

E. .1. DILZLMAN TROL MEANS THEREFOR Filed Feb. 5, 1940 HEATING SYSTEMSAND CON Patente-d Nov. 10, 1942 Earnest J. Dillman,

troit Lubricator HEATING SYSTEM AND CONTROL MEANS THEREFOR Detroit,Mich., assigner to De- Company, corporation of Michigan Detroit, Mich.,a

Application February 5, 1940, Serial No. 317,304

(Cl. 20G- 122) 25 Claims.

My invention relates generally to control devices and more particularlyto a room thermostat for controlling the temperature of an enclosedspace.

One of the objects of my invention is to provide means for controlling aheating apparatus thereby to maintain a predetermined temperature withinan enclosed space.

Another object is to provide means for changing the setting of theapparatus for maintaining a predetermined lower space temperature.

Another object is to provide a manually operable means for rendering thesetting changing apparatus ineffective.

Another object is to provide means for supplying additional heat to thethermostatc blade to compensate for overrun of the heating apparatus,which would unduly raise the temperature of an enclosed space.

A further object of the invention is to provide a new and noveltemperature controlling apparatus which is simple in operation andeconomical to manufacture.

The invention consists in the improved system and the construction andcombination of parts comprising the same, all as will be more fullydescribed hereinafter and the novelty of which will be particularlypointed out and distinctly claimed.

In the accompanying drawing, to be taken as a part of thisspecification, I have fully and clearly illustrated my invention, inwhich drawing- Figure 1 is a view in front elevation of the thermostatwith a portion of the cover broken away;

Fig. 2 is a view substantially along the line 2-2 of Fig. l and lookingin the direction of the arrows;

Fig. 3 is a view substantially along the line 3-3 of Fig. 1 and lookingin the direction of the arrows;

Fig. 4 is a partial view in rear elevation showing the adjustingmechanism:

Fig. 5 is a partial View in side elevation showing the means forsecuring the thermostat base to the mounting bracket;

Fig. 6 is a view substantially along the line 6-6 of Fig. 1 and lookingin the direction of the arrows;

Fig. '7 is a partial view in top elevation showing certain of theelements of the thermostat;

Fig. 8 is a partial view in side elevation showing the night turn-downswitch; y

Fig. 9 is a diagrammatic view of the apparatus connected to a heatingsystem;

Fig. 10 is a view of the heater switch blade, and

Fig. 11 is a partial view of a modified form of the thermostatic bladeand the carried contact member.

Referring to the drawing by characters of reference, the numeral Idesignates generally a base or supporting member which is preferablysubstantially rectangular in form and molded from an insulating materialsuch as Bakelite and the numeral Iu designates generally a cover membercooperable therewith. A fulcrum or bearing post 2 has one end securedwithin an aperture 3 extending through and located adjacent the lowerend 4 of the base member I, and has its other end extending outward fromthe front face 5 of the base member I and into the space enclosed by thecover member I a. An elongated, plate-like member 6 extends adjacent toand parallel to the face 5 and has at one end portion 6 a pair of spacedears or anges -I, 8 connected by a vertical portion 9. The ears 1, 8have aligned apertures which receive and journal about the post 2 tosecure the member 6 for rotational movement in a plane parallel to theface 5. The member 6 extends longitudinally of the member I and theother end I0 of the member 6 terminates adjacent the upper end II of andpreferably to the right of the longitudinal centerline of the member I.Journaled Within a tapered aperture I2 adjacent the end II, andsubstantially on the longitudinal centerline of member I, is a taperedportion I3 of a cam I4 which substantially fits the aperture I2. The camI4 is positioned adjacent the front face 5 of the base member I, and hasa metallic insert or shaft I-'Ia molded thereinto which extends throughthe portion I3 and outwardly from the rear face I5 of the base member Iand is threaded as at I4". A range adjusting or Calibrating screw I 6 isscrew-threaded through the side arms of a hook-shaped portion IIa of anupturned flange I 1 positioned at the end I0 of the member 6, andengages the face of the cam I 4. The side arms of the hook-shapedportion I6al are preferably held under a slight tension by the screw I6so that the screw is frictionally held in adjusted position. A helicallycoiled spring member I8 is positioned concentric with the post 2intermediate the spaced ears 1, 8 and has one end portion I9 positionedwithin an aperture in an outwardly projecting boss 20 of the base face 5and has its other end portion 2I extending longitudinally of andengaging an upturned flange portion 22 of the member 6. The springmember I8 acts to urge the plate-like member 6 in a counterclockwisedirection (see Fig. 1) to maintain the screw I6 in constant engagementwith the face of the cam I4 so that rotational movement of the shaft I4acan act through the cam I4 to move the member 6 in accordance with thesetting,r of the shaft |48. The portion 22 has a lead wire receiving lug22, the function of which will be set forth hereinafter.

The member 6 has intermediate its ends 6ut and I0, a rearwardlyprojecting lug 23 which ex- Ulli tends through a slot 24 in the basemember I so that a head portion which is normally spaced slightlyrearwardly of the rear face I5 cooperates with the face I5 to preventaccidental movement of the member 6 away from the front face. A metallicsupporting member 26 is positioned to the left of the longitudinalcenterline of the meinber I and has a horizontal portion 21 extendinglongitudinally of and held to the base member I by means of rivets 28,28a. The rivet 28 acts to electrically connect the member 26 to abinding post or screw 28b secured to the face I5. The member 26 has anupturned flange portion 29 having an L-shaped, offset extending portionhaving its short leg 38al perpendicular to the portion 29 and its longerleg 3i)b parallel to the portion 29. A shoulder 3I is formed at theintersection of the leg 38 with the portion 29, and a U-shaped permanentmagnet 32, which is preferably Alnico for high magnetism, is held withits poles spaced in a plane normal to the face 5 and facing toward thelongitudinal centerline of the member I. An inturned lug 33 of thevertical portion 29 rigidly clamps the magnet 32 against the leg 3U.

Spaced from the shoulder 3| and toward the end 4 of the base member I,the supporting member 26 has an upstanding ear or lug 34 to which issecured one end portion of a iiexible spring contact carrying blade 35,which blade extends longitudinally of the base member I and betweenpoles of the magnet 32, with the other end portion parallel to andlaterally spaced from the leg 30h. The blade 35 in its inert stateiiexes toward the leg 30b and away from the member 6, and is positionedor exed toward the member 6 by means of an adjustment screw member 36which in this instance is screw-threadedly secured to the leg 3Ilb andhas one end thereof engaging the blade 35. A contact member 31 isrigidly secured to the blade 35 and is positioned intermediate the polesof magnet 32, its position relative to the pole end faces beingdetermined by the member 36 which thereby acts to determine thetemperature differential at which the apparatus cperates.

A bimetallic strip or blade 38, which may be slightly tapered, has itswider end portion 39 secured to the vertical portion 9 of the plate-likemember 6 and the other or narrower en-d portion 40 ofthe bimetallicstrip 38 terminates substantially in the plane of the magnet 32. Asubstantially rigid metallic strip 4I, which in this instance is aboutonethird the length of the strip 38, has one end portion 42 secured tothe bimetallic end portion 40 and has its other end portion 43 extendingtoward the lower end 4 of the base member I, the portion 43 being spacedfrom the strip 38 toward the blade 35. The strip end portion 43 has alug or terminal 45 extending downward therefrom and toward the strip 38to serve as a. terminal for a exible lead wire. One end portion 46 of aflexible contact carrying blade 41 is secured to the portion 43, as bymeans of rivets. The other end portion 48 of the blade 41 is locatedintermediate the portion 40 and the contact member 31 and has securedthereto as by riveting, a contact member 49 which is cooperable toengage with the contact member 31 to control an electrical circuit. Apair of projections or ears extend outward from the strip end portion 42to form an armature 49l which cooperates with the magnet 32 to cause thecontact members 31, 49 to make and break the electrical circuitcontrolled thereby with a quick action. This quick action is partly madepossible by the flexibility of the bimetallic strip 38 and partly by theilexibility of the blade 41. A vibration dampening leaf spring 50extends spaced from and longitudinally of the blade 41 and has one endsecured to the end portion 46, and has an offset bent portion 5I at itsother end which normally engages the blade 41 approximately one-third ofthe dis tance between the contact member 49 and the blade end portion46. While the contact members 31, 49 are in engagement, the spring bentportion 5I is separated from the blade 41 and the riveted portion of thecontact member 49 is in engagement with the strip end portion 42. Upondisengagement of the contact members 31, 49 the blade 41 will flexoutwardly away from the end portion 42 and into engagement with the bentportion 5I of the spring 50. Engagement of the portion 5I by blade 41acts to dampen vibration of the contact member 49 thereby to prevent anyaccidental engagement upon opening of the contact members 31, 49.

Projecting rearwardly from the base member face I5 and adjacent the endportion II and the shaft threaded portion I4b is a lug 52 which ispreferably molded integral with the base member I. A plate member 53,which is positioned against the face I5 and concentric with the shaftI3, has a plurality of apertures therethrough, one of which receives thelug 52 to secure the member 53 against rotation and another of whichloosely receives the shaft I4. The plate member 53 is preferably locatedback of the base member I and so that it can not be seen when viewingthe front face 5, with the exception of a nger or pointer 54 whichprojects upward beyond the base member end II and which serves as anindicator. A disc-shaped dial plate 55 is positioned against themember'53 concentric with the shaft I4a which is received within acentral aperture extending through the dial plate 55. The dial plate 55is rigidly held against a shoulder on the shaft I4a by means of a nut 56threaded on the shaft portion I4J. An arc-shaped slot in the dial plate55 which may be of 180 as shown receives the lug 52, and cooperatestherewith to limit rotation of the dial plate 55. Projecting radiallyoutward from the circumference of the dial plate 55 is an extendingportion or knob 51 which is preferably so positioned that the pointer 54and knob 51 are in radial alignment when the instrument is set fornormal operation. Suitable indicia inscribed on the plate 55 cooperateswith the pointer 54 to indicate the temperature at which the contactmembers 31, 49 will engage to complete an electrical circuittherethrough. The dial plate 55 is frictionally held against unwantedrotation by a leaf spring 58 having one end portion held against thebase member face I5 by means of a screw 59 having its head positionedagainst the base member face 5 and extending through the base member Iso that the other or threaded screw portion will screw-threadedly engageand hold the spring 58.

Pivoted to the rivet 28 is one end of a platelike lever member 60 whichhas secured to its other end portion a heater carrying member 6I,preferably made of a strip of Bakelite. A pair cf clips 62, 63 areriveted one at each end portion of the member 6I and to the outer facethereof for receiving the end portions cf a cartridge type cylindricalheater'64. The clip 62 is electrically connected to the member 60through the rivet which secures the clip 62 and members 60, 6I together.The clip 63 is secured to the member 6I and electrically connected bymeans of a .rivet 61 to a plate-like member 66 which underlies one endportion of the member 6 I. The platelike member 66 has an upturned angeor ear 65 which extends perpendicular to the member' 8| and beyond theouter face thereof. A plate-like member 68 is rigidly secured againstthe base member face and within a conforming recess of an embossedsurface 68 by a rivet which also serves to connect electrically theplate member 88 to a binding screw or post 89 secured to the base memberface I5. The plate member 68 has a portion 10 bent upward into aposition substantially perpendicular to the face 5 and parallel to theear 86a. A screw 1I extends through an aperture in the portion 10 andhas its head end abutting the face of the portion 19 away from the ear66a. The threaded portion of the screw 1I is screw-threaded into athreaded aperture within the ear 68n aligned with the aperture inportion 1|). A helical coil compression spring 12 arranged concentricwith the screw 1I has one end abutting the portion 10 and its other endabutting the ear B6 so that the member 65 may be pivoted about the rivet28 by the screw 1I and thereby positioned relative to the bimetallicstrip 38. A pointer 14 which is integral with the member B6 cooperateswith suitable indicia on the member G8" to indicate the position of theheater 64 relative to the bimetallic strip 38.

Heat from the heater 64 is radiated directly to the strip 38 and is alsotransferred to the strip 38 through an arm or L-shaped portion 15 of theear 1 and through the vertical portion 9 which serves as a heatconducting member. One leg ol the L-shapcd portion is spaced from andoverlies the heater 64 and is tapered so that as the heater 64 is movedaway from the strip 38, less heat will be conducted through the portion15 to the strip 38.

For purposes of night turndown, so that the strip 38 will act to closethe contact members 31, 49 at a predetermined lower surroundingtemperature, there is provided a heater element 89 which is positionedadjacent to and to the right of the bimetallic strip 39, and is spacedfrom the front face 5. The heater preferably comprises a strip ofBakelite SI, or other electrical insulat ing material, which is notaffected by temperature and is clamped at either end to metalli-c spacermembers 82, 83 by means of screws 82a, 83e.

The spacer member 83 has a reduced portion extending through an aperturein the base member I and has a shoulder formed at the intersection ofthe reduced portion with the normal diameter portion which abuts theface 5 and positions the spacer member 83 relative to the member I. Thereduced diameter portion extends beyond the face 5 and extends throughan aperture in a plate 84 and the end portion is peened or riveted overto secure the member 83 within the base member aperture and the plate 84to the face I5. The plate 84 has a binding screw cr post 85 for securingthe thermostat lead wire. The spacer member 82 is substantially aU-shaped member having one of its leg portions turned outwardly, as at86, and apertured to receive a rivet 88a which extends through anaperture i1 the base member I and an aperture in a binding post or plate81. rigidly secure plate 81 and member 8 2 to the base, member I The endcf the other leg portion of the member 82 is received within an indentin the face 5 and is so positioned therein that when the screw securingthe strip 8I to the spacer mem- The rivet is peened over to ber 82 isrotated, the spacer member is held against rotation.

The leg portion which is received within the indent has a horizontaloffsetting portion which is apertured to receive a binding screw 88. Acoil of resistance wire 89 is wound around the strip 8| and has one endthereof secured to a clip which is positioned beneath the screw 83a andthe other end of the wire 89 is secured to contact member 90 which iscarried by the strip 8| intermediate the coil of wire and the member 83,and on the under surface thereof facing the face 5 of the member I. Aswitch blade 9|, which may be a piece of flexible, resilient, currentconducting metal, has one end secured intermediate the strip BI and thespacer member 82 by the screw 82e. The blade 9I extends substantiallyparallel to and beneath the strip 8I so that it underlies the contactmember 99 and cooperates therewith to control an electrical circuit. Theblade 9| has an offset portion 92 which is bent downwardly toward thebase member face 5 and cooperates therewith to limit the movement of theblade 9| in its opening direction and also serves as a cam face forcooperating with a slide member 98 carried by the cover member If. Themember 93 is slidable longitudinally of the member In parallel to theface 5 and along the cam face 92 to open and close the circuit to theheater element 80. A flange portion 94 of the member 93 is locatedintermediate the outside surface of the cover member Ia and the undersurface of a cap 95 carried by the member' I". A serrated externalportion 96 extends externally of the cap 95 through a slot 91 so thatthe switch may be operated manually externally or thel apparatus. Thecap 95 preferably contains suitable legendary matter so that the settingof the switch is clearly evident to persons operating the apparatus.

A mounting bracket |09 is preferably formed from a piece of plate stockharing flanged, longitudinal edge portions IIII and hook-like portionsI02 which extend outwardly and upwardly from: each flange portion IUI.The base member I has a pair of oppositely disposed side wall recesses13 which form shoulders H14. The recesses |93 receive the hook-likeportions |92 and the shoulders |04 cooperate therewith. to removablysecure the member I to the bracket Hi8. With this ofnstruction, thethermostat lead wires may be connected to the apparatus, and the bracketH18 secured to the room wall. prior to the securing rf the base member Ito the bracket |90 so that a completely concealed mounting is obtained.and one in which the cover member Ia nerd not be removed during theinstallation of the apparatm. This is particularly advantageous beca"seit eliminates the danger of accidental damage to tho delicate operatingparts of the thermcstatie epparatus.

There is but one lead wire I05 within the instrument, and this connectsthe binding scew 88 to either the lug 22a or the lus7 45, depending uponthe operating characteristics desired. If the instrument is to be usedon low amperag-e equipment which is generally the cesn in low voltagecircuits, it is preferable to secure the lead wire |05 to the lug 22" tominimize the resistance to movement of strip 38 and use the strip 38 acurrent conducting member. However. if the instrument is to be used onrelatively high amperage equipment, which is generally the case inhigher voltage circuits, the lead wire is connected to the lug 45 sothat the heating effect of the loro current flowing through the strip 38is eliminated.

The apparatus is connected into a control system by means of suitablelead wires. The binding post 81 is connected by the lead wire |25 to oneside of the secondary of a transformer |26. The other side of thesecondary is connected by a lead wire |21 to an electrically operatedheat supplying means |28 and by a lead wire |29 to one contact of a timeswitch |30. A lead wire |3| connects the lead wire |29 with a bindingpost 69 so that the transformer secondary is connected directly to themeans |28, time switch |30, and anticipatory heater 64. The other sideof the means |28 is connected by a lead wire |32 to binding post 28b andthe other side of the time switch |30 is connected by a lead wire |33 tothe binding post 85. The primary of the transformer |26 is supplied withelectrical energy through lead wires |34.

Fig. 11 shows a modification of my apparatus. The thermostatic blade 38ahas an offset end portion 40 which carries one edge portion of anon-heat-conducting, non-electrical-conducting plate-like member |40which may be a piece of Bakelite. The end portion 42a of the rigid strip4|n is secured to the opposite edge portion of the member |40. Aflexible lead wire |4| has one end (not shown) connected to the bindingscrew 88. The other end of the wire |4| is connected, as at |42, so thatit makes good circuit with the blade 41a and therethrough to the contactmember 49h. The wire |4| is clamped, as at |43, so that the wire isrigidly supported for movement with the blade 38t without mechanicalstrain at the connection |42. With this construction no current flowsthrough the bimetallic blade 38 and therefore the blade is not affectedby any internal heating effects due to the innate resistance of theblade to current flow. Furthermore, by electrically isolating the blade38 and platelike member 6 any capacity effect at open circuit conditionbetween the parts electrically connected with the contact member 31 andthe blade 38n and member 6 is eliminated.

When the contact members 31 and 49b are in engagement and current isflowing therethrough a certain amount of heat is generated due tocontact resistance. At circuit closed position the contact member 49b isin engagement with the rivets securing the portion 42 to the member |40`but the member |40, due to its resistance to heat flow, acts to preventany appreciable conduction therethrough to the sensitive bimetallicblade 38a.

The blade 38a therefore remains responsive to the temperature of thesurrounding air. With this construction, the apparatus may be utilizedto control circuits of relatively high currents and/or high voltageswithout a detrimental effect on the accuracy of the blade 38, It is seenthat the modification has certain advantages over the construction shownin the other figures.

The operation of my apparatus is as follows: Suitable lead wires areconnected as hereinbefore described to the binding screws 28h, 69, 85and 81. When the slide member 93 is moved to off position or the timeswitch |30 is in open circuit position, the apparatus then acts tocontrol an electrical circuit from the transformer |26, lead wire |25,binding post 81, its associated rivet, spacer member 82, lead wire tolug 22* then through strips 38 and 4|, blade 41, contact members 49, 31,blade 35, binding post 28b through its associated rivet, lead Wire |32,means |28, and lead wire |21. A circuit from the transformer |26 throughthe same path to blade 35 is also controlled by the contact members 49,31, but then the latter circuit goes through lever member 60, clip 62and its associated rivet, heater 84, clip 63 and its associated rivet,screw 1|, member 68, binding post 69 through its associated rivet, leadwire 3| and lead wire |29 to the transformer |26. In this manner theheater 64 is energized each time the contact members 31, 49 are closedso that the heater may anticipate the increased room temperature in thewell known manner, and its heat output is independent of the currentflowing through the means |28. Upon movement of the slide member 93downward or to on position, the blade 9| engages contact member 90 and acircuit is completed from the transformer |26, through lead wire |25,binding post 81, its associated rivet, spacer member 82, blade 9|,contact member 90, wire 89, spacer member 83, binding post through itsassociated rivet and to the time switch 30. Upon closure of the timeswitch |30 the circuit is completed through the lead wire |29 to thetransformer |26. The heater element 80 so energized acts to heat thestrip 38 so that it is maintained for example at 9 F. above ambienttemperature, thereby acting to temporarily maintain the room temperature9 F. below the setting of the dial plate 55. Upon movement of the slidemember 93 to off position, the heater element 80 is deenergized and thestrip 38 acts to control the contact members 31, 49 normallyirrespective of the switch |30.

It is to be noted that the disclosed construction is simple andeconomical for quantity manufacture, eliminates all inserts whichheretofore were molded within the base member thereby greatly decreasingthe manufacturing costs thereof. The disclosed construction alsoeliminates the need for an .extra night temperature sensitive blade, orfor a mechanical means to alter the normal daytime setting of the daytemperature sensitive blade. It may furthermore be noted that the switchblade 9| may be omitted and the terminals of the coiled heater wire 89connected directly one to each of the spacer members 82, 83 and the timeswitch |30 act to control the energization of the heater 80 therebyrendering the night turn-down entirely automatic without any means toprovide for abnormal operation.

The preferred embodiment of the device, however, is to have the timeswitch |30 energize the heater 80 at a regular predetermined time eachevening, and to deenergize the heater each morning at a regularpredetermined time. The manually operable slide member 90 is thenutilized as a means for preventing operation of the heater 80 upon thoseoccasions when it is desirable to maintain normal operation of thethermostat during the periods when the heater 80 would normally beenergized by the time switch |30. The member 90 thus enables theoperator to rbduy and simply render the time switch |30 ineffective toset the thermostat for night operation, upon certain occasions, withoutinterfering with the normal operation of the time switch per se orchanging the setting of the dial plate 55 to compensate for the effectof the heater 80.

What I claim and desire to secure by Letters Patent of the United Statesis:

1. In an apparatus of the character described, a base member, a movablesupporting member pivotally supported at one end thereof to one face ofsaid base member, a bimetallic element secured at one end portion tosaid supporting member, a rigid member secured to the other end portionof said bimetallic element and having its free end extending toward saidelement one end, a flexible carrying member secured to the free end ofsaid rigid member and having a portion extending toward said elementother end portion, a contact member carried by said fiexible member atsaid iiexible member portion, said iiexible member being operable toallow relative movement between said contact member and said element,and adjusting means on said base member on the face opposite to said oneface, said adjusting means having a portion extending 'through said basemember and operable lto vary the temperature at which said contact.'member will complete an electric circuit.

2. In an apparatus of the character described,

base member, a movable supporting member votally supported at one endthereof to one face of said base member, a bimetallic element secured atone end portion to said supporting member, a xed contact member carriedby said base member on said once face, a rigid member carried by theother' end portion of said bimetallic element, a flexible contactcarrying member carried by said rigid member and having a portionadjacent said element other end portion, a movable contact membercarried by said flexible member at said flexible member portion, saidflexible member' being operable to allow relative movement between saidmovable contact member and said element, adjusting means on said basemember on the face opposite to said one face, said adjusting meanshaving a portion extending through said base member, said extendingportion having a cam operable upon movement of said adjusting means toengage and to move said supporting member to vary the temperature atwhich said movable contact member will engage said fixed Contact member,and means tending to follow said movable Contact member to dampenvibration of said movable. contact member subsequent to disengagement ofsaid contact members.

3. In an apparatus of the character described, a base member, a movablesupporting member pivotally supported at one end thereof to one face ofsaid base member', a bimetallic element secured at one end portion tosaid supporting member, a xed contact member carried by said base memberon said one face, a rigid member carried by the other end portion ofsaid bimetallic element, a flexible contact carrying member carried bysaid rigid member and having a portion adjacent said element other endportion, a movable contact member' carried by said flexible member atsaid flexible member' portion, said flexible member being operable toallow relative movement between said movable contact member and saidelement, adjusting means on said base member on the face opposite tosaid one face, said adjusting means having a portion extending throughsaid base member and operable to vary the temperatur'e at which saidmovable contact member will engage said fixed contact member, means todampen vibration of said movable contact member subsequent todisengagement of said contact members, a horse-shoe type permanentmagnet having its poles embracing said fixed contact member and carr1ed'by said base member, and armature means carried by said rigid memberand cooperable with said magnetic means to cause said movable contactmember to move with a quick action 4. In an apparatus of the characterdescribed,

CII

Search iieom a base member, a contact member carried by said basemember, a thermostaticelement carried by said base member, a Contactmember carried by said element, a heat supplying means, a heatconducting member secured in heat conducting relationship to saidelement for conducting heat supplied by said heat means to said elementand having a portion positioned adjacent said heat means, and means forvarying the rate of heat transfer to said element from said heatsupplying means.

5. In an apparatus of the character described, a base member, a contactmember carried by said base member, a thermostatic element carried bysaid base member, a contact member carried by said element, a heatsupplying means, a heat conducting member for conducting heat suppliedby said heat supplying means to said element and having a portionpositioned adjacent said heat means, and means for moving said heatsupplying means relative to said conducting member portion thereby tovary the rate of heat transfer therethrough from said heat supplyingmeans to said element.

6. In an apparatus of the character described, a base member, a contactmember carried by said base member, a thermostatic element carried bysaid base member, a contact member carried by said element, a heatsupplying means, heat conducting means for transferring heat from saidheat'I supplying means to said element, said conducting means having aV-shaped portion adjacent said heat supplying means, and means formoving said heat supplying means with respect to said V-shaped portionthereby to vary the rate of heat transfer from said heat supplying meanso said element. 7. In an apparatus of the character described,

` a casing, a thermostatic element carried by said casing, a Contactmember carried by said casing, a contact member carried by said elementand cooperable with said rst-named contact member' to control anelectrical circuit, electrical heater means within said casing anddisposed in heat exchange relation with said element, a fixed contactmember, a movable contact member, iiexible means having a portionthereof rigid with said casing and carrying said movable contact memberand operable to urge said movable contact member in one direction, saidfixed and said movable contact members being operable to control anelectrical circuit to said heater means, and means slidably secured to awall of said casing and manually movable from external of said casingfor iiexing said carrying means in a direction opposite to said onedirection thereby to control the operation of said heater means.

8. In an apparatus of the character described, a casing comprising abase member and a cover member, a thermostatic element carried by saidbase member, a contact member carried by said base member, a contactmember carried by said element and cooperable with said first-namedcontact member to control an electrical circuit, electrical heater meansdisposed in heat exchange relation with said element and carried by saidbase member, a fixed contact member carried by said heater means, alongitudinally extending plate-like member underlying said heater meansand having a portion cooperable with said xed contact member andoperable to control an electrical circuit to said heater means, saidcover member being cooperable with said base member to enclose saidelement and said heater means, and means carried by said cover member,said last-named means having a portion extending through said covermember and being cooperable with said plate-like member to move saidplate-like member in one direction and having a portion extendingexternal of said cover member so that said plate-like member may bemoved from externally of said casing.

9. In an apparatus of the character described, a casing comprising abase member and a cover member, a carrying member spaced from andsecured to said base member within said casing, a contact member carriedby said carrying member within said casing, electrical resistance meanscarried by said carrying member within said casing and having oneterminal thereof secured to said contact member, a movable member withinsaid casing and extending adjacent to said carrying member and having aportion thereof cooperable with said contact member to control anelectric circuit to said resistance means, and means carried by saidcover member for moving said movable member.

10. In an apparatus of the character described, a casing comprising abase member and a cover member, a carrying member spaced from andsecured to said base member within said casing, a contact member carriedby said carrying member within said casing, electrical resistance meanscarried by said carrying member within said casing and having oneterminal thereof secured to said contact member, a movable member withinsaid casing and extending adjacent to said contact member to control anelectric circuit to said resistance means, said movable member havingone end portion secured intermediate said base member and said carryingmember, and means carried by said cover member and movable substantiallyparallel to said carrying member for moving said movable member.

11. In an apparatus of the character described, a casing comprising abase member and a cover member, a strip insulating member spaced fromand secured to said base member within said casing, a contact membercarried by said strip member within said casing, electrical resistancemeans carried by said strip member within said casing and having oneterminal thereof secured to said contact member, a resilient plate-likecurrent conducting member within said casing and extending adjacent tosaid strip member and having a portion thereof cooperable with saidcontact member to control an electric circuit to said resistance means,said plate-like member having one end portion secured intermediate saidbase member and said strip member, said plate-like member having anoffset stop portion at its other end portion, said stop portion beingengageable with said base member to limit movement of said plate-likemember away from said contact member, and means carried by said covermember portion and movable substantially parallel to said strip memberfor moving said platelike member.

12. In an apparatus of the character described, a base member, anadjustable temperature sensitive element carried by said base member andmovable in a plane substantially parallel to said base member, arotatable member carried by said base member, cam means having a camface in a plane substantially parallel to said base member and operableby said rotatable member and cooperable with and to regulate theadjustment of said element, said rotatable member extending through saidbase member, and a manually operable member rigidly secured to saidrotatable member and operable to actuate said cam means, said basemember having a portion interposed between said manual member and saidcam means.

13. In an apparatus of the character described, a base member having anaperture therethrough, a temperature sensitive element carried on oneface of said base member through which said aperture extends, a memberrotatable in said aperture and having a portion extending beyond saidone face and having a portion extending beyond a second face of saidbase member through which said aperture extends, a cam member secured tosaid rotatable member rst-named portion and cooperable with said elementupon rotation to adjust the operation of said element, a wheel-likemember secured to said rotatable member second-named portion and havinga portion viewable upon viewing said one face, said wheel-like memberhaving suitable indicia on said viewable portion, a pointer membercooperable with said indicia for determining the setting of saidelement, and means carried by said wheel-like member and extendingradially therefrom, said extending means being constructed and arrangedrelative to said pointer member so as to indicate the normal setting ofsaid wheel-like member when said extending means is in alignment withsaid pointer member.

14. In a device of the character described, a base member, a carryingmember pivotally supported on said base member, a contact member carriedby said base member, a bimetallic blade having one end portion securedto said carrying member, a non-conducting member secured to the otherend portion of said blade and positioned adjacent said contact member, arigid member carried by said non-conducting member, and a resilientlymounted contact member carried by said rigid member and cooperable withsaid carried contact member to control an electric circuit.

15. In a device of the character described, a supporting member, aswitch arm having one end portion carried by said member, an insulatingmember secured to said arm, a rigid metallic strip member carried bysaid insulating member, and a resiliently mounted contact member carriedby said rigid member, said contact member being engageable with saidrigid member to limit movement of said contact member in one directiorelative to said rigid member.

16. In a switch mechanism, a pair of longitudinally extendingsubstantially parallel metallic contact carrying members, a contactmember carried by one of said members, a second contact member carriedby the other of said parallel members and cooperable with saidfirst-named contact member to control an electric circuit, and aninsulating member carried by said other parallel member, said secondcontact member being electrically insulated from said other parallelmember by said insulating member thereby to reduce the capacity effectbetween said parallel members when said contact members are in opencircuit position.

17. In an apparatus of the character described, a base member, atemperature sensitive member, means having movement in a plane parallelto and carried by said base member on one face thereof and supportingsaid sensitive member for movement in a plane parallel to said one Iace,a fixed contact member, a U-shaped permanent magnet carried by said basemember on said one face, means having movement in a plane parallel toand carried by said base member on said one face and extending betweenthe poles of said magnet, said last-named means being operable toposition said fixed contact member between said magnet poles andadjustably position said fixed contact member relative to the faces ofsaid magnet poles, a movable contact member carried by said sensitivemember and cooperable with said fixed contact member to control anelectric-circuit, and adjusting means carried by said base member on theface opposite to said one face, said adjusting means having a portionextending through said base member, said extending portion having a camsurface operable upon rotation of said adjusting means to move saidsensitive member supporting means parallel to said one face thereby tovary the temperature at which said movable contact member will engagesaid fixed Contact member.

18. In an apparatus of the character described, a base member, acont-act member carried by said base member, a thermostatic elementcarried by said base member' and having a portion engageable with saidcontact member to complete an electric circuit, a heat supplying means,a heat conducting means extending into relatively close overlyingrelation to said supplying means and for transferring heat from saidheat supplying means to said element, and means for moving one of saidmeans relative to the other of said means so that the rate of transferof heat to said heat conducting means from said heat supplying means maybe varied.

19. In a device of the character described, a base member having anupper and a lower surface, a fulcrum pin carried by said base member atone end portion thereof and extending from and substantiallyperpendicular to said upper surface, a longitudinally extending levermember fulcrumed on said pin and extending toward the end portion ofsaid base member opposite to said one end portion, said base memberhaving an aperture therethrough opening through said surfaces, saidlever member having a rebent portion adjacent said aperture, anadjustment member rotatable in said aperture and having a cam portionparallel to and adjacent to said upper surface, an adjustment pinscrew-threadedly secured to said rebent portion and having an endsurface portion engaging said cam portion for movement of said levermember in a plane parallel to said upper surface upon rotation of saidadjustment member, an elongated bimetallic strip member secured at oneend portion to said lever member and extending along said upper surfacetoward said opposite end portion, a first contact member carried by saidbimetallic member at the end portion thereof opposite to said one endportion and having movement relative thereto, a U- shaped permanentmagnet carried by said upper surface and having its poles aligned in aplane extending vertically to said upper surface, a second contactmember, means positioning said second contact member intermediate saidpoles and in position for engagement by said first contact memberthereby to complete an electric circuit, and an armature member carriedby said bimetallic member and cooperable with said magnet to cause saidcontact members to engage with a quick action, means rigid with said rstcontact member and engageable with said armature, member subsequent toengagement of said first contact member with said second contact memberthereby to limit the movement of said arma- Search Room ture membertoward said magnet to prevent a positive engagement of said armaturemember with said poles.

20. In a device of the character described, a

ase member having an upper and a lower surface, a fulcrum pin carried bysaid base member at one end portion thereof and extending from andsubstantially perpendicular to said upper f surface, a longitudinallyextending lever member fulcrumed on said pin and extending toward theend portion of said base member opposite to said one end portion, saidbase member having an aperture therethrough opening through saidsurfaces, said lever member having a rebent portion adjacent saidaperture, -an adjustment member rotatable in said aperture and having acam portion parallel to and adjacent to said upper surface, anadjustment pin screw-threadedly secured to said rebent portion andhaving an end surface portion engaging said cam portion for movement ofsaid lever member in a plane parallel to said upper surface uponrotation of said adjustment member, an elongated bimetallic strip membersecured at one end portion to said lever member and extending along saidupper surface toward said opposite end portion, a first contact membercarried by said bimetallic member at the end portion thereof opposite tosaid one end portion and having movement relative thereto, a U-shap'edpermanent magnet carried by said upper surface and having its polesaligned in a plane extending vertically to said upper surface, a secondcontact member, means positioning said second contact memberintermediate said poles and in position for engagement by said firstcontact member thereby to complete an electric circuit, an armaturemember carried by said bimetallic member and cooperable with said magnetto cause said contact members to engage with a quick action, means rigidwith said first contact member and engageable with said armature membersubsequent to engagement of said first contact member with said secondcontact member thereby to limit the movement of said armature membertoward said magnet to prevent a positive engagement of said armaturemember with said poles, and means for adjustably positioning relative tothe face of said poles the face of said second contact member which isengaged by said first contact member thereby to determine the movementof said armature member toward said poles.

21. In a device of the character described, a base member having anupper and a lower surface, a fulcrum pin carried by said base member atone end portion thereof and extending from and substantiallyperpendicular to said upper surface, a longitudinally extending levermember fulcrumed on said pin and extending toward the end portion ofsaid base member opposite to said one end portion, said base memberhaving an aperture therethrough and extending through said surfaces,said lever member having a rebent portion adjacent said aperture, anadjustment member rotatable in said aperture and having a cam portionparallel to and adjacent to said upper surface, an adjustment pinscrew-threadedly secured to said rebent portion and having an endsurface portion engaging said cam portion for movement of said levermember in a plane parallel to said upper surface upon rotation of saidadjustment member, an elongated bimetallic strip member secured at oneend portion to said lever member and extending along said upper surfacetoward said opposite end portion, a first contact member, meansresiliently securing said first contact member to said bimetallic memberand carried by said bimetallic member at the end portion thereofopposite to said one end portion, a U-shaped permanent magnet carried bysaid upper surface and having its poles aligned in a plane extendingvertically to said upper surface, a second contact member, meanspositioning said second contact member intermediate said poles and in aposition for engagement by said first contact member thereby to completean electric circuit, an armature member carried by said bimetallicmember and cooperable with said magnet to cause said contact members toengage with a quick action, said first contact member having a portionengageable with said armature member subsequent to engagement of saidfirst contact member with said second contact member thereby to limitthe movement of said armature member toward said magnet to prevent apositive engagement of said armature member with said poles, and meansengageable with and movable with said resiliently securing means upondisengagement of said contact members to dampen vibration of said firstcontact member.

22. In an apparatus ot' the character described, a base member, asupporting member having a portion held against said base member andhaving an upturned flange, said flange having one portion and having asecond portion bent to form a shoulder with said one portion and havinga third portion extending beyond said second portion substantiallyparallel to said one portion, a U-shaped permanent magnet carried bysaid supporting member adjacent said shoulder with the poles of saidmagnet in vertical alignment relative to said base member, saidsupporting member having a second fiange on the side of said magnetopposite to said third flange portion, a resilient blade member havingone end portion secured to said second ange and extending between saidmagnet poles and overlying said third flange poi'- tion, a contactmember carried by said blade member intermediate said poles, and meanscarried by said third ange portion for positioning the contact face ofsaid contact member relative to the face of said poles.

23. In an apparatus of the character described, a base member, asupporting member having a portion held against said base member andhaving an upturned flange, said ange having one portion and having asecond portion bent to form a shoulder with said one portion and havinga third portion extending beyond said second portion substantiallyparallel to said one portion, a U-shaped permanent magnet positionedadjacent said shoulder with the poles of said magnet in verticalalignment relative to said base member, tab means extending from saidfirst flange portion and locking said magnet in position against saidshoulder, said supporting member having a second flange on the side ofsaid magnet opposite o said third flange portion, a resilient blademember having one end portion secured to said second ange and extendingbetween said magnet poles and overlying said third fiange portion, acontact member carried by said blade member intermediate said poles, andmeans carried by said third flange portion for positioning the contactface of said contact member relative to the face of said poles.

24. In an apparatus of the character described, a plate-like basemember, a plate-like supporting member secured in face to face relationwith said base member and having an upstanding flange, a U-shaped magnetheld against said ange with its poles in vertical alignment relative tosaid base member, a blade member having one end portion secured to saidplate-like supporting member` and extending substantially parallel tothe upper face of said base member and intermediate the poles cf saidmagnet, a contact member carried by said blade member intermediate saidpoles, means carried by said ange and engageable with said blade memberfor positioning said contact member relative to the end surfaces of saidpoles, a plate-like elongated arm member having one end portionpivotally secured to said supporting member and extending therefromtoward one end portion of said base member, a bimetallic strip membercarried by said base member and extending from said base member one endportion substantially parallel to said base member upper face, a contactmember carried by said bimetallic member and cooper-able with saidfirst-named contact member to control an electric circuit, armaturemeans carried by said bimetallic member and cooperable with said magnetto cause said contact members to break said circuit with a quick action,heater means having heat exchange relation with said bimetallic memberand carried by said elongated arm member, and means carried by said basemember and operable to pivot said elongated arm member thereby t0position said heater means relative to said bimetallic member.

25. In an apparatus of the character described, a plate-like basemember, a plate-like supporting member secured in face to face relationwith said base member and having an upstanding fiange, a U-shaped magnetheld against said flange with its poles in vertical alignment relativeto said base member, a blade member having one end portion secured tosaid plate-like supporting member and extending substantially parallelto the upper face of said base member and intermediate the poles of saidmagnet, a contact member carried by said blade member intermediate saidpoles, means carried by said fiange and engageable with said blademember for positioning said contact member relative to the end surfaceof said poles, a plate-likeelongated arm member having one end portionpivotally secured to said supporting member and extending therefromtoward one end portion of said base member, a bimetallic strip membercarried by said base member and extending from said base member one endportion substantially parallel to said base member upper face, a contactmember carlied by said bimetallic member and coopeiable with saidfirst-named contact member to control an electric circuit, armaturemeans carried by said bimetallic member and cooperable with said magnetto cause said contact member to break said circuit with a quick action,electrical heater means having heat exchange i elation with saidbimetallic membeil and carried by said elongated arm member, meanscarried by said base member and operable to pivot said elongated armmember thereby to position said heater means relative to said bimetallicmember, said last named means acting as an electrical conductor for saidheater means, and spling clip means holding said elongated arm member ingood electrical contact with said supporting member.

EARNEST J. DILLMAN..

